Arch, particularly for use in metallurgical furnaces



April 18, 1933. w. ALBERTS 1,904,596

ARCH, PARTICULARLY FOR USE IN METALLURGICAL FURNACES Filed Dec. 7, 1929 Fig. 1

Fig.2

Inventor".- Wa/f 14/17/45 4 Patented Apr. 18, 1933 UNITED STATES PATENT OFFICE WALTER ALBEBTS, OF DUISBURG-RUHRORT, GERMANY, ASSIGNOBIII To FIRM VEREINIGTE STAHLWERKE AKTIENGESELLSCHAFT, 0F DUSSELDORF, GERMANY ARCH, PARTICULARLY FOR USE IN METALLURGICAL FURNACES Application filed December 7, 1929, Serial No. 412,373, and in Germany July 4, 1929.

This invention relates to arches for metallurgical furnaces of the class wherein the arch or upper portion thereof is built up of fire bricks which present a relatively uniform and smooth face toward the interior of the furnace and exteriorly have projections which provide the furnace exteriorly 7 It is therefore a prime desideratum of the art to render the arch of a furnace which is severely attacked by the action of the hot gases as resistant as possible in order to prolong its life and to avoid expensive repair work and renovations.

The arch of a furnace will be capable of successfully resisting the action of hot gases longer and better, the more intense the action of the cooling means provided as a compensating medium, the degree of the cooling ac- Therefore, the question is to make the air contacting surface of the arch which is not in contact with the fire and which constitutes the principal cooling means, as large as possible and-to give it the shape best suited for the purpose. I V

Tests have already been made in this direction. Thus, in constructing arches, bricks had been used having the gradually tapering crosssection of a trapezoid on their outer surfaces, whereby a more rapid radiation of the heat of the bricks into the atmosphere was expected to occur.

J However, such a construction is accompanied by various disadvantages which render the value of this arrangement doubtful.

When an arch of a furnace is composed of bricks of such a profile; between the ribs formed by the trapezoid-like reductions,

narrow angular spaces will result which, instead of promoting the heat exchange between the arch and the atmosphere, will cause eddy currents and will block the radiation of the heat. In other words, bricks of such a profile do not serve the expected purpose.

It is the object of the present invention to produce an arch particularly for use in metallurgicalfurnaces whose exposed outersurface is shaped in such a way as to make possible under all circumstances a rapid radiation of the heat of the arch into the atmosphere. V

According to the practice of the present invention, this desirable result is now acof shaped bricks having profiles of two or more types on their outer air contacting or exposed surfaces, that is, of modified or curved configuration, seam the exterior of the arch which is out of contact with the fire gases is provided with alternately adjacent ridges of awave and depressions between the waves.

In order to 'obtain'all the benefit possible from a large outer radiating surface of an arch of this character, it is indispensableto use bricks which have special profiles involving rounded surfaces and which may be arranged ,in such a way as to assume a wavelike configuration. In this way the outer surface of an arch will not only be enlarged to an complished by constructing the furnace arch extraordinary degree, but in consequence of the great width of the depressions between the waves formed by arranging side by side differently curved bricks, a rapid radiation of the heat will be secured. By giving the ridges of the waves a point-likeshape the heat exchange will be considerably accelerated, since,naturally, the thinnest partof the mass of the bricks will cool, off the quickest.

In the annexed drawing one embodiment of the invention 'is illustrated by way of ex arch composed of such bricks.

As may be seen from the drawing, the exposed genera-l surface formed by the combined furnace bricks aand b which have a difi'erently curved configuration on their exterior 5 radiating or air contacting surface, including points 0 as well as a plurality of depressions d curved in generally concave profile whose width may vary according to the order in which the various bricks have been laid.

This construction of a furnace arch makes possible in a very advantageous manner a rapid radiation of the heat of the bricks into the air without setting up eddy currents or blocking the emanation of the heat, since the width of the depressions between the waves may be chosen at will.

Having thus described my invention what I claim as new' and desire to secure by Letters Patent is:

2 1. In a furnace of the class indicated, an

arch which is built up of bricks individually having profiles of a plurality of types of curved configuration on the surface of the arch which is out of contact with the fire and exposed to the air, the bricks being arranged in such manner that the outer surface of the arch presents an undulated surface comprising a series of peaks and depressions While the inner surface of the arch is generally smooth.

2. In a furnace, an arch according toclaim 1 in which the bricks provide differently curved configurations on the outer surface of the arch and are arranged in varied order so that the surface of the arch which is out of contact with the fire presents various profiles.

3. In a furnace of the class indicated, the combination, with an arch built up of bricks and having interior-1y a generally smooth surface exposed to the fire, of undulated curved configurations provided on the individual bricks forming said arch upon the exterior surface of the latter which is out of contact with the fire and directly exposed to the air,

the bricks being arrar ged in such relative order that said outer surface of the arch presents an undulated surface comprising a plurality of peaks and intermediate depressions.

WALTER ALBERTS. 

